usb: gadget: tegra-xudc: Add usb-phy support

usb-phy is used to get notified on the USB role changes. Get usb-phy from
the UTMI PHY.

Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com>
Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/usb/gadget/udc/tegra-xudc.c b/drivers/usb/gadget/udc/tegra-xudc.c
index 077f83c..1ee6138 100644 (file)
--- a/drivers/usb/gadget/udc/tegra-xudc.c
+++ b/drivers/usb/gadget/udc/tegra-xudc.c
@@ -26,7 +26,9 @@
 #include <linux/reset.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
+#include <linux/usb/otg.h>
 #include <linux/usb/role.h>
+#include <linux/usb/phy.h>
 #include <linux/workqueue.h>
 
 /* XUSB_DEV registers */
@@ -487,6 +489,9 @@ struct tegra_xudc {
        bool suspended;
        bool powergated;
 
+       struct usb_phy *usbphy;
+       struct notifier_block vbus_nb;
+
        struct completion disconnect_complete;
 
        bool selfpowered;
@@ -669,6 +674,31 @@ static void tegra_xudc_usb_role_sw_work(struct work_struct *work)
                tegra_xudc_device_mode_off(xudc);
 }
 
+static int tegra_xudc_vbus_notify(struct notifier_block *nb,
+                                        unsigned long action, void *data)
+{
+       struct tegra_xudc *xudc = container_of(nb, struct tegra_xudc,
+                                              vbus_nb);
+       struct usb_phy *usbphy = (struct usb_phy *)data;
+
+       dev_dbg(xudc->dev, "%s(): event is %d\n", __func__, usbphy->last_event);
+
+       if ((xudc->device_mode && usbphy->last_event == USB_EVENT_VBUS) ||
+           (!xudc->device_mode && usbphy->last_event != USB_EVENT_VBUS)) {
+               dev_dbg(xudc->dev, "Same role(%d) received. Ignore",
+                       xudc->device_mode);
+               return NOTIFY_OK;
+       }
+
+       xudc->device_mode = (usbphy->last_event == USB_EVENT_VBUS) ? true :
+                                                                    false;
+
+       if (!xudc->suspended)
+               schedule_work(&xudc->usb_role_sw_work);
+
+       return NOTIFY_OK;
+}
+
 static void tegra_xudc_plc_reset_work(struct work_struct *work)
 {
        struct delayed_work *dwork = to_delayed_work(work);
@@ -1937,6 +1967,9 @@ static int tegra_xudc_gadget_start(struct usb_gadget *gadget,
                xudc_writel(xudc, val, CTRL);
        }
 
+       if (xudc->usbphy)
+               otg_set_peripheral(xudc->usbphy->otg, gadget);
+
        xudc->driver = driver;
 unlock:
        dev_dbg(xudc->dev, "%s: ret value is %d", __func__, ret);
@@ -1957,6 +1990,9 @@ static int tegra_xudc_gadget_stop(struct usb_gadget *gadget)
 
        spin_lock_irqsave(&xudc->lock, flags);
 
+       if (xudc->usbphy)
+               otg_set_peripheral(xudc->usbphy->otg, NULL);
+
        val = xudc_readl(xudc, CTRL);
        val &= ~(CTRL_IE | CTRL_ENABLE);
        xudc_writel(xudc, val, CTRL);
@@ -3558,9 +3594,15 @@ static int tegra_xudc_probe(struct platform_device *pdev)
        INIT_DELAYED_WORK(&xudc->port_reset_war_work,
                                tegra_xudc_port_reset_war_work);
 
-       /* Set the mode as device mode and this keeps phy always ON */
-       xudc->device_mode = true;
-       schedule_work(&xudc->usb_role_sw_work);
+       xudc->vbus_nb.notifier_call = tegra_xudc_vbus_notify;
+       xudc->usbphy = devm_usb_get_phy_by_node(xudc->dev,
+                                               xudc->utmi_phy->dev.of_node,
+                                               &xudc->vbus_nb);
+       if (IS_ERR(xudc->usbphy)) {
+               err = PTR_ERR(xudc->usbphy);
+               dev_err(xudc->dev, "failed to get USB PHY: %d\n", err);
+               goto free_eps;
+       }
 
        pm_runtime_enable(&pdev->dev);